Why Most Founders Overestimate Product-Market Fit

Product-Market Fit (PMF) is not a feeling; it is a set of objective signals. Overestimating it can be a fatal mistake for early-stage founders.

False Positives

• Network Love: Buying because they trust you personally, not because of market-leading value.
• Polite Feedback: "This is a great idea" is not a buying signal. Contracts are.
• Happy Niche Customers: Finding a few users with a unique problem that doesn't scale.

Product-market fit is when your customers start selling for you.

The Real Signals

1. The Sean Ellis Test: At least 40% of users would be "very disappointed" without you.
2. Organic Pull: Non-trivial growth from word-of-mouth and referrals.
3. Retention & Expansion: Existing customers paying you more over time.

The Takeaway

Be ruthless in questioning your traction. Wait for objective evidence that the market is pulling the product from you before you pour gasoline on the fire.